“I am just looking at the “big-picture” using all available data while considering feedbacks that have been incorrectly considered (or unidentified) and in the context of abrupt changes that are CLEARLY documented in climate paleorecords.

I really hope I’m wrong folks but I just don’t see it any other way. Time will tell…”

#10 know-nothing infant, Mirabella is deeply unpopular with her electorate because she is incompetent and lazy. She has been losing her margin since she was given what used to be a safe seat. On LOCAL issues she is a failure, and her conservative electorate have had enough of her arrogance and poor performance as a local member. Green issues have nothing to do with it. She has been outcampaigned by a committed local candidate who has the backing of many figures who by ordinary political persuasion would be Coalition voters.

Bernard!
Snork away all you like
It makes very little difference to the overall result of the election. Nick is correct that Mirabella has become unpopular locally. McGowan is supported by conservative votes. You appear to be clutching at straws with that snork.

Limits in detecting acceleration of ice sheet mass loss due to climate variability

“The Greenland and Antarctic ice sheets have been reported to be losing mass at accelerating rates1, 2. If sustained, this accelerating mass loss will result in a global mean sea-level rise by the year 2100 that is approximately 43 cm greater than if a linear trend is assumed2.

However, at present there is no scientific consensus on whether these reported accelerations result from variability inherent to the ice-sheet–climate system, or reflect long-term changes and thus permit extrapolation to the future3.

Here we compare mass loss trends and accelerations in satellite data collected between January 2003 and September 2012 from the Gravity Recovery and Climate Experiment to long-term mass balance time series from a regional surface mass balance model forced by re-analysis data.

We find that the record length of spaceborne gravity observations is too short at present to meaningfully separate long-term accelerations from short-term ice sheet variability.

We also find that the detection threshold of mass loss acceleration depends on record length: to detect an acceleration at an accuracy within ±10 Gt yr−2, a period of 10 years or more of observations is required for Antarctica and about 20 years for Greenland.

This para is worth repeating……………
“However, at present there is no scientific consensus on whether these reported accelerations result from variability inherent to the ice-sheet–climate system, or reflect long-term changes and thus permit extrapolation to the future”

“…at present there is no scientific consensus whether these reported accelerations result from etc….” The question posed is: is observed short-term acceleration a reflection of a long term loss trajectory or is it natural variability superimposed on a steady ice loss trend? We want to know because we want to estimate future loss and SLR.

There is consensus that Antarctica is losing mass due to climate change,and the evidence is ample in the lit. and mechanisms explained up thread.

“Our SMB reconstructions indicate that the SMB changes over most of Antarctica are statistically negligible and that the current SMB is not exceptionally high compared to the last 800 yr. High-accumulation periods have occurred in the past, specifically during the 1370s and 1610s. However, a clear increase in accumulation of more than 10% has occurred in high SMB coastal regions and over the highest part of the East Antarctic ice divide since the 1960s.”

#17 moron, higher snow accumulation periods in a supercold environment will occur with warming climate,at elevation while at sea level SMB can fall…it may as well be shit dribbling to slow types like yourself,it’s all the same to you: too complex.

Snow accumulation at altitude in the WAP was seen to increase with rise in atmospheric moisture,even while coastal shelves collapsed and lower glaciers accelerated and lost surface height. It’s a dynamic system not some two-dimensional sketch.

Yet another paper you have not understood! Wouters et al. is about detecting an acceleration in ice mass loss. Nobody – and I do mean nobody – disputes that there is a substantial and ongoing ice mass loss from both the GIS and the WAIS. The critical question here is that it is difficult to say if it is now accelerating because the observational data only exist for short periods.

Now, here’s the thing. Most glaciologists think that the rate of ice mass loss *is* accelerating, but being good scientists, they need to demonstrate the acceleration rigorously. At present, this is not really possible because you can argue that some sort of natural variability is responsible for the *apparent* acceleration. Longer observational data sets required.

You also fail to understand the Zwally study. You have conflated the WEST Antarctic Ice Sheet with the EAST Antarctic Ice Sheet. The former is losing mass at a rapid (and probably accelerating) rate while the latter is gaining mass because of increased precipitation, widely accepted to be a consequence of AGW. Zwally points out that increasing mass loss from the WAIS will initiate a contribution to SLR within the decade. This is a near-universal expectation. When, not if.

It’s also worth noting that the latest research suggests that parts of the EAIS (Wilkes Subglacial Basin) are much more sensitive to warming than previously thought, which provides the so-far elusive physical mechanism for early/mid-Pliocene sea level highstands at least 10m above present levels.

No, it wasn’t global and synchronous. Lots of episodes of regional cooling, offset by simultaneous episodes of regional warmth elsewhere. Pointing to two decade-long periods in the past when SMB increased briefly is evidence of nothing at all except increased *regional* precipitation over Antarctica. SMB isn’t even a proxy for cool temperatures, you dozy muppet.

“We find that data from climate model reanalyses are not able to characterise the contemporary snowfall fluctuation with useful accuracy and our best estimate of the overall mass trend—growth of 27±29 Gt yr−1—is based on an assessment of the expected snowfall variability. Mass gains from accumulating snow, particularly on the Antarctic Peninsula and within East Antarctica, exceed the ice dynamic mass loss from West Antarctica. The result exacerbates the difficulty of explaining twentieth century sea-level rise. ”

“Satellite radar altimetry measurements indicate that the East Antarctic ice-sheet interior north of 81.6°S increased in mass by 45 ± 7 billion metric tons per year from 1992 to 2003. Comparisons with contemporaneous meteorological model snowfall estimates suggest that the gain in mass was associated with increased precipitation. A gain of this magnitude is enough to slow sea-level rise by 0.12 ± 0.02 millimeters per year. ”

Karen, I know you are sitting there with ClimateDepot or similar, just clicking through the tags for “Antarctic” or similar and spamming. I *know* this. Just as I know you are stupid, ignorant and insane.

What “Karen” is too stupid to understand is that this is a *dynamic* process (see Nick #18). SMB gain in parts of the EAIS interior is currently possible because outflow glaciers are plugged by embayed ice shelves or firmly grounded. But this is already changing.

Advected warm water is increasing the rate of basal melting of ice shelved right around the continent. Rates differ, but this is the shape of things to come because the laws of physics say so. See here.

Once the ice shelves begin to break up, the rate of drainage by outflow glaciers increases very rapidly, and the dynamics of SMB gain and IMB loss reverse.

Poor Karen, lost in spam and lies, cannot understand the basic concept.

“Advected warm water is increasing the rate of basal melting of ice shelved right around the continent. Rates differ, but this is the shape of things to come because the laws of physics say so. See here.”

so this has never happened before ?

lol…. the nuttery is astounding, bbd did you just find that at dotearth?

Past climate change isn’t all determined by CO2. This is just denialist fuckwittery. *You* are confused.

Let’s take the Eemian. Orbital dynamics made the Eemian warmer than the Holocene – but not by much. Global average temperature was ~1 – 2C warmer but MSL during the Eemian was *at least* 5m higher than the Holocene. Where did all that extra water come from?

The GIS and the WAIS. People who *know* about this know that the latest work (NEEM) suggests that the GIS contributed *no more* that ~2m to the MSL highstand, so the rest came from the WAIS (where else – an alternative universe?).

Past global climate changes had strong regional expression. To elucidate their spatio-temporal pattern, we reconstructed past temperatures for seven continental-scale regions during the past one to two millennia. The most coherent feature in nearly all of the regional temperature reconstructions is a long-term cooling trend, which ended late in the nineteenth century. At multi-decadal to centennial scales, temperature variability shows distinctly different regional patterns, with more similarity within each hemisphere than between them. There were no globally synchronous multi-decadal warm or cold intervals that define a worldwide Medieval Warm Period or Little Ice Age, but all reconstructions show generally cold conditions between ad 1580 and 1880, punctuated in some regions by warm decades during the eighteenth century. The transition to these colder conditions occurred earlier in the Arctic, Europe and Asia than in North America or the Southern Hemisphere regions. Recent warming reversed the long-term cooling; during the period ad 1971–2000, the area-weighted average reconstructed temperature was higher than any other time in nearly 1,400 years.

“There were no globally synchronous multi-decadal warm or cold intervals that define a worldwide Medieval Warm Period or Little Ice Age, but all reconstructions show generally cold conditions between ad 1580 and 1880,”

lol

sorta like now there is global warming, but not in Antarctica, but, really trooly woolie it is global

East Antarctica is thermally isolated by the Antarctic Circumpolar Current, fuckwit. The West Antarctic Peninsula is not. The WAP is warming up at a cracking pace, as is well known except amongst denialist buffoons.

And now back to #38, which Karen is going to deal with, like it or not:

Past climate change isn’t all determined by CO2. This is just denialist fuckwittery. *You* are confused.

Let’s take the Eemian. Orbital dynamics made the Eemian warmer than the Holocene – but not by much. Global average temperature was ~1 – 2C warmer but MSL during the Eemian was *at least* 5m higher than the Holocene. Where did all that extra water come from?

The GIS and the WAIS. People who *know* about this know that the latest work (NEEM) suggests that the GIS contributed *no more* that ~2m to the MSL highstand, so the rest came from the WAIS (where else – an alternative universe?).

Hopefully it will be over soon? ?????????
So you do now say there is a hiatus?
Why are you hoping it will be over BBD?
SUUUURRRRREEEELLLLYYYYY it would be better if all the doomsday predictions/projections are incorrect??????

#57 at the climate scale,what hiatus? Oh, of course, that little daft meme of yours.
#58,the ‘stooopid reason’ being the state of the cryosphere and organic matter revealed across the NH by glacial retreat. Ignorant /play dumb Kaz.

#62,well that proves it’s not warming: one data point in early spring…yes I think we can dismiss all the thousands of other data points,this ones a cracker! Very Steve Goddard of you Kaz, the shucks-its-a cold-day counter…only available to the cream of the absolute idiots.

#63,I just am not up to speed on glacial organic remnants in the SH, where glaciers are secretly [to you apparently] retreating at_a_cracking_pace. Let me apologise for not doing your work for you,dimwit.

problemo……….you don’t know what the high temp of the holocene was, for some stooopid reason you think that it is hotter now.

Too stupid for words. See Marcott et al. (2013):

Our results indicate that global mean temperature for the decade 2000–2009 (34) has not yet exceeded the warmest temperatures of the early Holocene (5000 to 10,000 yr B.P.). These temperatures are, however, warmer than 82% of the Holocene distribution as represented by the Standard 5×5 stack, or 72% after making plausible corrections for inherent smoothing of the high frequencies in the stack (6) (Fig. 3). In contrast, the decadal mean global temperature of the early 20th century (1900–1909) was cooler than >95% of the Holocene distribution under both the Standard 5×5 and high-frequency corrected scenarios. Global temperature, therefore, has risen from near the coldest to the warmest levels of the Holocene within the past century, reversing the long-term cooling trend that began ~5000 yr B.P.

BB the Holocene would have been as warm as the Eemian except for the intrusion of the Younger Dryas, which acted as a damper.

Utter fucking bollocks. Go away and do some reading. Start with orbital dynamics. Then move on to causes of the YD. Then look at climate dynamics. Try to understand what “quasi-equilibrium” actually means. How could an event like the YD depress GAT for the rest of the Holocene? Physical mechanism… oh don’t bother. Idiot.

#68,Gordy’s Gambit was priceless..the first ‘original’ material I’ve seen from him….though it does smell a bit like something you’d see in a Jo Nova thread. Or Monckton might blurt that sort of thing out before a suitably moronic audience.

Charles Darwin recognised these for their roles in evolution in turn building on the work of Charles Lyell. Indeed Darwin had a copy of Lyell’s ‘Principles of Geology’ with him on HMS Beagle, I trust you have some knowledge of Darwin and the Beagle. Indeed Lyell’s book gave Darwin valuable insights when the Beagle stopped at St Jago, now Santiago in the Cape Verde Islands (Portugal)

Once again you are caught spouting crap from a position of ignorance. When will you stop doing this and start broadening your education.

You could start with Darwin’s’ ‘Voyage of the Beagle’ and ‘Origin…’ if you have not already. Bill McGuire’s ‘Waking the Giant: How a changing climate triggers earthquakes, tsunamis, and volcanoes‘ contains much enlightenment and some food for thought.

…you will discover that he introduced the complaint about blogs being ‘advocacy blogs’. I was just pointing out that this blog is an advocacy blog too.

I don’t think you and Jeff are using the term the same way.

a) Jeff’s comment was talking about blog posts by the blog owners (and those they choose to invite to write posts).

You are drawing a false equivalence by comparing that with commenters here, and a small subset of commenters here at that.

b) In addition Jeff appears to be using “advocacy blog” to describe one that advocates for particular (policy or political) position, often cloaking itself in pseudo-science in an attempt to mislead many of their readers that their positions are derived from science.

Referring back to point (a), the blog posts here aren’t doing that (and weren’t even doing that back when the posts consisted of more than Open Thread posts)

And moving past (a) to look at the commenters here, the only commenters doing that kind of advocacy and claiming (pseudo-scientific) support for it here are the self-styled “skeptics”. You skipped right over their “advocacy” and instead focused on Jeff based on his use of certain words with political connotations. You have not shown that he is engaging in advocacy based on pseudo-science – and you can’t, because he is careful to cite the mainstream science, especially in areas outside of his own scope of scientific competence. So once again you’ve drawn a false equivalence.

Total ocean heat content has increased by around 170 Zettajoules since 1970, and about 255 Zettajoules since 1955. This increased temperature has caused the oceans (0-2,000 meters) to warm about 0.09 C over this period. As the UK’s Met Office points out, if the same amount of energy had gone into the lower atmosphere it would of caused about 36 C (nearly 65 degrees F) warming! The oceans are by far the largest heat sink for the Earth, absorbing the vast majority of extra heat trapped in the system by increasing concentrations of greenhouse gases.

Lionel… Isostatic uplift during the RWP seems less likely than thermal expansion to explain SLR.

BB the CO2 content in the atmosphere remained steady during the Younger Dryas, so we can safely assume temperatures fell sharply and rose again without any assistance from carbon dioxide.

Gordy, you haven’t spotted your own idiocy yet! Go back and look at #79.

If thermosteric SLR raised sea levels *universally* as you claim, then we should see global evidence of a sharp fall in MSL – everything – not just a couple of Roman harbour, should be “high and dry”. Idiot.

Second point. I asked you for evidence for a global and synchronous Roman Warm Period. You haven’t provided *any*. Ditto for this supposed “Minoan Warm Period”.

Now, I’ve got Gornitz here in front of me, and nowhere in all its 1000 pages is there a reference to the “Minoan Warm Period” or the “Roman Warm Period”. Nowhere.

But if I google these terms, lots of disinformer blogs pop up. Lots of liars and shills and idiots. Now that ought to tell you something important about just how far from mainstream paleoclimatology this all is. You are living in a fantasy world created by liars and shills and idiots. Wake up, Gordy.

Third point. You, like the abysmally stupid “Karen” are clinging with all your might to a strawman. *Nobody* is claiming that all past climate change was caused by CO2. That is why I asked you to get off your lazy arse and find out about the causes of the YD. Which you obviously haven’t bothered to do, preferring instead to post fuckwittery on the Internet.

For the last time, I don’t care how many fucking stations there are. It is utterly fucking irrelevant. If I wanted to know I would find out, in under 30 seconds, but I can’t even be bothered. Especially since you are mithering me about it.

You have been shown up to be utterly clueless on topics that *do* matter, over and over again. You cannot read graphs. You cannot understand basic scientific modes of thinking. You deny evidence. You deny physics.

You are a worthless pile of lunatic shite bubbling away in a cellar somewhere. Sane people aren’t interested in your lunatic gibbering.

Isostatic uplift during the RWP seems less likely than thermal expansion to explain SLR

Anyone who studied geography in early high school years knows about isostatic rebound (especially in Scotland where it is a well known phenomenon). He doe not realize that it is the land which is rising during isostatic rebound, not the sea.

Up today at DesmogBlog in ‘Dealing in Doubt: Greenpeace Report Exposes Fossil Fuel Funded Climate Denial Machine‘ pointing to information on the denial machine with some right-on graphics across the top of every page, with Joseph Bast in the line up at left and Richard Lindzen at right. Lindzen must be proud to be so aligned with Bast – the pinnacle of a scientific career, what!

This latest report is an expanded and updated one since the last in 2010, just in case you think you already have it.